Depends upon the area. Ursula K. LeGuin, in a preface to her science fiction novel "The Left Hand of Darkness" wrote "It is an artist's job to say that which cannot be said in words. A novelist is an artist whose medium is words. That is, it is a novelist's job to say, in words, that which cannot be said in words! To do this, we use a technique called 'the lie'."

If your school or local library offers access to JSTOR, there is a terrific paper on this written by Thomas Merrill called Milton's Satanic Parable about the use specifically of parable as a means of informing the attitude rather than the intellect. The use of myth and folklore, and even children's tales, has a long history of shaping the belief systems, and perhaps more importantly, the ethics and ideal behavior of persons socialized into a given culture where that myth or tale originates. The article uses Paradise Lost as a point of reference, but this notion of certain literature as parabolic language can be applied generally.